Question

If the current value of the PC is 0x1FFFf000, can you use a single jump instruction to get to the PC address as shown in Exercise 2.39?

Short answer

Yes, since the range is $0\times 1FFDF004~0\times 2001F000$

Step-by-step solution

Determine the MIPS jump instruction

The MIPS assembly language has the j instruction to perform the jump. The address of the target will be reached through jump only if the target address lies within the jump range. The range of the address can be calculated by adding the word length and the program counter value with the starting range.

For example:

j 3500

The above instruction will jump to the target address.

Determine whether the single jump instruction will be enough to get to the PC address.

The given value of PC is 0x1FFFf000.

For the jump instruction the address range can be calculated as follows:

Let us consider the register values from the exercise 2.39 as given in the question.

Range:

$$\begin{gathered} PC+4+0\times 1FFFC=0\times 1FFFf000+4+0\times 1FFFC \\ =0\times 2001F000 \end{gathered}$$

The value of PC is added with the base register value and the value of register from exercise 2.39 is added.

$$\begin{gathered} PC+4-0\times 02000000=0\times 1FFFf000+4-0\times 02000000 \\ =0\times 1FFDF004 \end{gathered}$$

The above is the range of the jump instruction.

So, Yes single jump instruction can be used, because the range of the jump is$0\times 1FFDF004~0\times 2001F000$